The present invention relates generally to management of computer networks. The invention relates more specifically to a method and apparatus for identifying characteristics of client modems in a managed network.
A computer network typically includes one or more server elements that service client entities based upon requests or instructions from the client entities. In a dial-up network configuration, a client entity may include a client application that can communicate with the server entities through a client signal modulator-demodulator (xe2x80x9cclient modemxe2x80x9d). A server entity can include, or have between it and the client entity, an access server which can perform one or more operations based upon signals being sent to the server entity, for example from the client entities. For example, in the process of communication between the client entity and the server entity, the client modem may send a signal that is received by the access server. The access server then utilizes information of the signal to facilitate communication between the client entity and the server entity.
In some instances, the communication between the client and server entities can fail. This may be due to one or more of several possible factors. For example, the communication failure can be due to characteristics of one of the devices in the signal path between the client and server, such as the client modem. However, a network manager cannot always determine why, where, or how the failure occurred. In this context, xe2x80x9cnetwork managerxe2x80x9d refers broadly both to persons responsible for network management, and network management software or systems.
Even if the category of failed device (e.g., the client modem) is suspected or known to contribute to the failure, the specific type of device within that category may not be known. For example, in a distributed system where the client is not under the same control as is the server, it may be impossible to determine what type of modem failed, only that some modem failed. In internetworking, for example, certain Internet Service Providers (ISPs) may be unwilling to disclose what kind of modems are used in their facilities.
If a network manager could determine the specific manufacturer or model of a modem that has failed or contributed to a failure, then the network manager could target modems of that manufacturer or model for testing, repair, improvement, accommodation, or other management.
Modems that transmit data at 56 kilobits (Kb) per second using the V.90 standard are now widely used in network computing. V.90 is a standard, approved by the International Telecommunications Union (ITU), for transmitting data downstream to modems at 56 Kbps. However, presently, there is no practical way to determine what manufacturer is associated with a failed or failing client modem that is connected to a server using a V.90 connection.
Based on the foregoing, there is a clear need in this field for a method and system for identifying a network device.
In particular, there is a need for a method or apparatus that can identify the make or model of a modem in a network that has failed or is suspected of contributing to a failure. There is a specific need for such a method or apparatus that operates in conjunction with modems that interacted with access servers in managed networks. There is an additional need to provide such a method and system while minimizing complexity and maximizing efficiency.
The foregoing advantages, and other advantages that will become apparent from the following description, are achieved by the present invention, which comprises, in one aspect, a method and apparatus for identifying one or more characteristics of a networked device, such as a client modem. Values of one or more components, of a signal from an unknown device are compared to values of the same components of signals from known devices. Matches determined by this comparison identify characteristics, such as the manufacturer or model, of the unknown devices to be the same as characteristics of the matched known devices. The comparison values are determined by receiving signals from known devices, and identifying and cataloging values of the one or more signal components in association with characteristics of the known devices. The identified characteristics are stored and later can be accessed or manipulated to derive additional information, such as statistical information based on the characteristics identified for multiple unknown devices.
In one aspect, the invention provides a method of determining and storing a value of a characteristic of a device in a network, comprising the steps of receiving a signal from the device, wherein the signal is uniquely characterized by at least one signal parameter; identifying at least one value of at least one pre-selected signal parameter in the signal; and determining, based on a reference table that associates device characteristics with signal parameters, at least one characteristic of the device.
In another aspect, the invention provides a method of determining a manufacturer associated with an V.90 modem in a network, the method comprising the computer-implemented steps of receiving a message from the modem during a Training Phase of an V.90 session between the modem and a router; identifying a DIL descriptor in the message received from the modem; comparing a Sign Pattern value and a Training Pattern value of the DIL descriptor to a reference table that associates DIL descriptor values with manufacturer information; and determining the manufacturer associated with the V.90 modem based on matching manufacturer information in the reference table.
The foregoing should be understood as merely a brief summary of selected aspects and features of the invention that does not limit the scope of the invention. Many other features and aspects that are not summarized here will become apparent from the following detailed description.